User interface for a portion of a display screen



The FIGURE is a front view of a user interface for a portion of a display screen showing our new design.

The broken line drawing of a portion of a large rectangle and the broken line drawings of the three smaller rectangles are for illustrative purposes only and form no part of the claimed design. The areas within the small rectangles are not part of the claimed design. The broken line right and bottom edges of the shaded area are unclaimed boundaries. The broken line drawing of a portion of a display screen is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a user interface for a portion of a display screen, as shown and described. 